The fields of nanoscience and nanotechnology concern the synthesis, fabrication and use of elements and systems at atomic, molecular and supramolecular levels. The nanoscale of these elements and systems offers significant potential for research and applications across the scientific disciplines including materials science, engineering, physics, chemistry, computer science and biology. Although active uses of heat to alter geometries, structures or properties in conventional processes often involve macroscale elements or systems, fundamental technical constraints can hinder comparable nanoscale approaches. For example, in structural materials, heat treatment of nanograined metals obtained by severe plastic deformation or sintering of nanopowders into bulk consolidates can be limited by in-process grain growths. Generally, such limitations arise due to characteristic lengths and times of heat transfer in macroscale elements and systems, which are incompatible with spatial or temporal dimensions on the nanoscale. To date, there remains a need for elements and systems on the nanoscale that can enable both fine local heat selectivity and time-exposure control. Such elements and systems may be used in nanoscale manufacturing or on-board thermal actuation and autonomous powering during operation of nanosized devices.